Though there is enough food produced in the world to feed everyone, logistical and political problems make its distribution inefficient. At the current rate of world population growth, we may soon have to change our eating habits and eat more grain and less meat. There is a limited amount of grain that the Earth can produce. Currently, much of this grain is consumed by cattle, rather than humans. If humans were to eat the grain instead of eating the cattle, the calories from the grain would be twenty times more efficient than those from beef.